80 bulletin: museum of comparative zoology. 



among " forms with cylindrically rooted teeth. " J The only author who has ar- 

 gued against an association with Platanistids, as commonly understood, is Prof. 

 J. F. Brandt, who concluded from the general aspect of the skull and form of the 

 teeth that it approached very closely the existing Whitefish, Delphinapterus leucas. 

 He even questioned the propriety of regarding it as the type of a distinct genus : 

 " Der Schadel ahnelt offenbar dem von Delphinapterus leucas. Als Typus einer 

 eigenen Gattung mbchte ich sie daher, wenigstens vorlaufig, noch nicht gelten 

 lassen." 2 Within recent years Dr. Othenio Abel has reiterated the same opin- 

 ion. 3 Thus the matter stands at the present time. 



It may be well to present here Cope's original definition of the genus, to 

 which nothing has since been added. This is given as follows : 



LOPHOCETUS Cope. 



" Temporal fossa truncated by a horizontal crest above, prolonged backwards 

 and bounded by a projecting crest, which renders the occipital plane concave. 

 The same crest prolonged upwards and thickened, each not meeting that of the 

 opposite side, but continued on the inner margins of the maxillary bones, turning 

 outwards and ceasing opposite the nares. Front, therefore, deeply grooved. 

 Premaxillaries separated by a deep groove. Teeth with cylindric roots." 



Lophocetus calvertensis (Harlan). 



1842. Delphinus calvertensis Harlan, Bull, of Proc. Nat. Inst., p. 195, Plates, 1-3. 



1842. Delphinus calvertensis Dekay, Nat. Hist. N.Y. Zool. pt. 1, p. 136. 



1842. Delphinus calvertensis Markoe, LTnstitut, 10, p. 384. 



1866. Pontoporia calvertensis Cope, Proc. Acad. Nat. Sci. Phil., p. 297. 



1867. Lophocetus calvertensis Cope, Proc. Acad. Nat. Sci. Phil., p. 144, 146. 

 1869. Lophocetus calvertensis Leidy, Joum. Acad. Nat. Sci. Phil., (2) 7, p. 435. 

 1873. Lophocetus calvertensis Brandt, Mem. Acad. Imp. Sci. St. Petersb., (7) 20, 



p. 288. 



1880. Lophocetus calvertensis Van Beneden and Gervais, Osteographie des Ceta- 

 ces, p. 512. 



1890. Lophocetus calvertensis Cope, Amer. Nat., 24, p. 606, 615. 



1896. Lophocetus calvertensis Roger, Verzeichniss fossiler Saugethiere, p. 79. 



1899. Lophocetus calvertensis Abel, Denksehr. k.k. Akad. Wissench., 68, p. 869, 



873. 



1902. Lophocetus calvertensis Hay, Bull. 179, U. S. Geol. Surv., p. 590. 



1904. Lophocetus calvertensis Case, Maryland Geol. Surv. Miocene, 26, p. 9, 



Plates 16, Fig. 1. 



The type specimen consists of a well-preserved skull, from which the lower jaw 

 and forward extremity of the muzzle are wanting. There are preserved besides all of 



1 Maryland Geological Survey, Miocene, 1904, p. 9. 



2 Die fossilen und subfossilen Cetaceen Europa's. Me'm. Acad. Imp. Sci. St. 

 Petersb., (7) 1873, 20, p. 288. 



3 Fossile Platanistiden des Wiener Beckens. Denksehr. k.k. Akad. Wissensch., 

 1900, 68, p. 869. 



